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Why it's difficult to accurately test the efficiency of a plug-in car

When it comes to electric vehicles and plug-ins in general, the Environmental Protection Agency-certified range is a hugely important number. While actual range anxiety is largely psychological, the magic number does provide a point of comparison of buyers considering one EV over another. The driving distance is also often touted by automakers when marketing their models. Unfortunately, as Green Car Reports finds in a recent deep dive, the way the EPA calculates the figure is a convoluted mess, and discovering the reasons why is definitely worth the read. The issue isn't about bad science but instead comes down to vague wording. The EPA's accepted range test is sourced from an evaluation called J-1634 from the Society of Automotive Engineers, and it seems to provide balanced results for vehicles that automatically reach a single state of charge when plugged in. However for models with multiple charge settings, the situation gets complicated very quickly. Of course, these modes are often created in the software, meaning that a car's certified driving distance can change with just a few taps of the keyboard without the real world results owners might experience actually changing. By showing the test's effects on the certified range for the Tesla Model S, Nissan Leaf and Mercedes-Benz B-Class Electric Drive over the last few years, Green Car Reports makes a compelling argument that it's the evaluation that needs to change. Thankfully, it appears that the solution is a very simple one. Get the details here.

MotorWeek proves '90s were awesome with Supra, Stealth, RX-7, Corvette, 968, 300ZX comparo

Oh, the heady days of 1993, back when the Clinton Presidency was just getting underway, and it seemed like every hot new rock band was coming out of Seattle. Sports cars in the US had finally shaken off the shackles that slowed them during the '70s and '80s, and you could buy any number of legitimately quick vehicles again. MotorWeek recently went digging into its archives to find this six-model test from 1993 showing off some of the best semi-affordable performance coupes that money could buy at the time, and it's priceless.
Featuring the 1994 model year Toyota Supra in twin-turbo guise and MY 1993 versions of the Porsche 968, Nissan 300ZX TT, Mazda RX-7, Dodge Stealth R/T Turbo and Chevrolet Corvette LT-1, MotorWeek definitely covered all of the bases. One thing that might surprise younger readers is these cars' performance. The video only provides 0-60 acceleration times, but several of these vehicles would still be considered pretty potent today - over 20 years since going on sale. The Supra is especially impressive, hitting 60 miles per hour in just 5 seconds. Even today, that's nothing to sneeze at.
Given their performance potential and still-attractive looks, it's amazing that some of these coupes are old enough to drink now. The progress of interior design and safety equipment in the intervening years is pretty shocking, though. In most of these models, having two airbags is touted as a big deal. Scroll down to watch a Throwback Thursday blast from the past about some of the '90s best sports cars.

Is the skill of rev matching being lost to computers?

If the ability to drive a vehicle equipped with a manual gearbox is becoming a lost art, then the skill of being able to match revs on downshifts is the stuff they would teach at the automotive equivalent of the Shaolin Temple. The usefulness of rev matching in street driving is limited most of the time – aside from sounding cool and impressing your friends. But out on a race track or the occasional fast, windy road, its benefits are abundantly clear. While in motion, the engine speed and wheel speed of a vehicle with a manual transmission are kept in sync when the clutch is engaged (i.e. when the clutch pedal is not being pressed down). However, when changing gear, that mechanical link is severed briefly, and the synchronization between the motor and wheels is broken. When upshifting during acceleration, this isn't much of an issue, as there's typically not a huge disparity between engine speed and wheel speed as a car accelerates. Rev-matching downshifts is the stuff they would teach at the automotive equivalent of the Shaolin Temple. But when slowing down and downshifting – as you might do when approaching a corner at a high rate of speed – that gap of time caused by the disengagement of the clutch from the engine causes the revs to drop. Without bringing up the revs somehow to help the engine speed match the wheel speed in the gear you're about to use, you'll typically get a sudden jolt when re-engaging the clutch as physics brings everything back into sync. That jolt can be a big problem when you're moving along swiftly, causing instability or even a loss of traction, particularly in rear-wheel-drive cars. So the point of rev matching is to blip the throttle simultaneously as you downshift gears in order to bring the engine speed to a closer match with the wheel speed before you re-engage the clutch in that lower gear, in turn providing a much smoother downshift. When braking is thrown in, you get heel-toe downshifting, which involves some dexterity to use all three pedals at the same time with just two feet – clutch in, slow the car while revving, clutch out. However, even if you're aware of heel-toe technique and the basic elements of how to perform a rev match, perfecting it to the point of making it useful can be difficult.